CA2235253A1

CA2235253A1 - A hot fill container

Info

Publication number: CA2235253A1
Application number: CA002235253A
Authority: CA
Inventors: David Lee Carew; Peter Robert Mckinlay
Original assignee: Individual
Current assignee: Amcor Pty Ltd
Priority date: 1995-10-19
Filing date: 1996-10-11
Publication date: 1997-04-24
Also published as: EP0859718A4; EP0859718A1; AU720439B2; BR9610866A; NZ319076A; AUPN605595A0; WO1997014617A1; US6044996A; JPH11513639A; AU7122096A

Abstract

A hot fill container formed from a polymeric material is disclosed. The container comprises a base (4), a body (2), and neck (1), wherein the body (2) comprises an odd number of spaced-apart panels (5) that are responsive to internal pressure changes in the container. Hot fill bottles of a given capacity having an uneven number of deformable panels e.g., five of a given wall thickness unexpectedly accommodate significantly higher volume reductions before collapsing and distorting in an uncontrolled manner than known hot fill bottles of the same capacity having an even number of panels e.g., six of the same wall thickness.

Description

CA 0223~2~3 1998-04-17 A ROT FILL CON~ATN~

The pre~ent invention relate~ to pla~tic container~ which are ~uitable ~or receiving a hot f ill product.

The term "contA;~e~" is underAtood herein to mean any type of cont~;n~, including, but not limited to, bottles a~d jars.

The preaent invention relate~ particularly, althou~h by no mean~ exclusi~ely, to hot fill bottles $ormed ~rom blow-moulded ~olyester re~in.

Hot f ill bottles are well known in the liquid Fackagin~ indu~try. ~n ~eneral terms, hot f ill bottle~ are bottles that are filled with a liquid ~roduct that ix hot, typically at lea~t 80~C, and thereafter are ~ealed while the li~uid i~ hot in order to provide adequate ~terili~ation.

Commo~ly, hot fill bottle~ are blow moulded from polyester re~in and other suitable polymeric materials and com~riqe a base, a generally cylinarical body, a ~houlder, and a neck.

Hot fill bottle~ manufactured from blow moulded polye~ter resin do not expand significantly on ~on~ct with hot liquid. However, a~ hot liquid C0018, u~ually it con~racts and thereby creates a ~artial vacuum in the sealed bottle~. The ~artial vacuum generates inward forcès on the walls of the bottle~. ~nle~s the inward force~ are re~isted by the ~tructure of the bottle~ or the ~hape o~
the bottles change in a controlled -~ in re~pon~e to the inward forces, there i~ uncontrolled distortion of the CA 0223~2~3 1998-04-17 W097/14617 PCT/~U96/00641 walls of the bottles.

In many situation~, uncontrolled di~tortion of hot fill bottles regultg in the bottles havin~ a mis-~hapen/buckled a~pearance which consumers assume is an indication that the bottles are damaged, and thereby detract~ from the marketability of the bottles.

In order to avoid uncontrolled distortion of the walls of hot f ill bottles, a known ty~e of hot fill bottle com~rises an even number of circumferentially spaced conca~e panelR arranged in diametrically opposed ~airs in the cylindrical body of the bottle. The concave panels do not resist the internal ~ressure change~ as hot li~uid cool~ in the bottle but respond to the changes by flexing or deforming inwardly a~ hot liquid in the sealea bottles contracts as it cools in the bottles.
-Whilst this known ty~e of hot fill bottle is ableto accommodate ty~ical volume reduction~ in current hot-fill applications, the concave panels form a ~ignificant part of the body of the bottle and provide ;nA~e~uate su~port for a label to be wrapped around the bottle. In marketing termg, this is a gigni~icant disadvantage of the bottle.

As a consequence, a known modified hot fill bottle comprises concave panels having central raised label ~u~port sections which define contact areas for label~.

The use of the label support section~ addres~es the need to ~rovide su~ficient contact area ~or label~.
However, a di~advantage i~ that the label sup~ort sections~
are relatively rigid and reduce the volume that can be accommodated by the panels - with the effect on volume reduction being directly related to the relative surface areas of the label ~upport gection~ and the concave CA 0223~2~3 1998-04-17 ~ection~ of the ~anels.

It ha~ been found that the maximum volume reduction that can be accommodated by commercially available hot fill bottle~ having label ~up~ort ~ection~ is clo~e to the typical volume reduction of li~uids that occur~ in current hot-fill application~ when the liquid~
cool from hot fill temperatures (at least 80~C) to ambient temperature. A~ a con~equence, in ~ractice, it has been foun~ that the ~anel~ of a ~ignificant ~ercentage of the commercially available hot fill bottle~ are not able to move inwardly sufficiently to accommodate the reductions in volume an~, con~equently, theQe bottle~ collap~e an~
~i~tort in an uncontrolled m~nner.

One ~o~sible ~olution to thi~ ~roblem i~ to increa~e the wall thickne~ of the hot fill bottles.
~owever, thi~ ~olution carrie~ with it a relatively high economic co~t due to ad~itional raw material~ and han~ling coc lt~ .

An object o$ the present invention i~ to provide a hot fill bottle which avoidQ the problem of uncontrolled ~i~tortion of the wall~ of the bottle.

According to the pre~ent invention there i~
provi~ed a hot fill container $ormed from a polymeric material, which cont~; n~ comprise~, a ba~e, a body, and a neck, wherein the body compri~e~ an o~d number of ~paced-apart panel~ that are re~ponsive to internal pre~ure change~ in the container.
I

It i~ pre$erre~ that the panels be re~pon~ive to~
internal pres~ure changes within the co~t~; ne~ that occur when, in u~e, the cont~;ne~ i~ fille~ with a hot liqui~ at a temperature of at lea~t 80~C, more preferably at least 85~C, sealed, and the li~uid cools to ambient temperature~

CA 0223~2~3 1998-04-17 thus reducin~ the volume defined by the contA; ner, The pre~ent invention ig ba~ed on the unexpected f;n~;ng of the a~licant that hot fill bottles of a given capacity having an uneven number of deformable panels of a given wall thicknes~ can accommoaate significantly higher volume reauctions before collap~ing and ai~torting in an uncontrolled -nn~ than known hot fill bottles of the same ca~acity having an even number of ~anels of the same wall thicknes~.

In the case of 500 m~ capacity bottle~ filled with liquia at a temperature of at least 80~C, preferably at least 85~C, it i~ preferred that the panels be adapted to accommodate volume reauctions of at least 25 mL a~ the hot-filled container cool~ to ambient temperatures.

In the case o~ 750 m~ capacity bottles filled with liquid at a temperature o~ at least 80~C, preferably at least 85~C, it i~ preferred that the ~anelQ be adaptea to accommodate volume reauctions of at lea~t 36 mL as the hot-filled container cools to ambient temperatures.

In the ca~e of l litre capacity bottles fillea with liquia at a temperature of at least 80~C, ~referably 85~C, it i~ preferrea that the ~anels be aaapted to accommoaate volume reauctions of at least 45ml as the hot-~illed container cools to ambient temperatures.

It i~ preferred that the cont~; ne~ be blow moulded .

It i~ preferred that the body be generally cylindrical.

With such an arrangement it is preferred that the panelQ be spaced apart arouna the circumference of the CA 0223~2~3 1998-04-17 WO97/1~617 PCT/AU96/00641 body. --It i~ preferred particularly that there be a uni~orm ~pacin~ between the panels.

In one embo~; ~nt, it i~ preferred that the bo~y com~rise~ 5 panel~.

It i~ preferred ~articularly that the bo~y com~rises 5 panel~ when the ca~acity of the cont~; ne~ i~
less than l litre.

In another preferred embodiment it i~ preferred that the body compri~es 7 panel~.

It i~ preferrea ~articularly that the body com~ri~e~ 7 panel~ when the capacity of the cont~; ne~ i~
equal to or greater than l litre.

The panel~ may be of any ~uitable configuration which i~ a~apted to be re~ponsive to change~ in internal pre~ure in the container.

In one embodiment, it is preferred that the panel~ comprise panel wall~ that are adapted to flex or deform inwardly.

With ~uch an arrangement, it is preferred that the panel wall~ be conca~e.

In another embodiment, it i8 preferred that the panels comprice label ~up~ort ~ection~ that are relatively ri~id and hin~e a~semblie~ that interconnect the label ~upport ~ection~ and adiacent ~ection~ of the body and allow the label ~upport ~ection~ to move inwardly.

It i~ preferred that the panel~ be axially CA 0223~2~3 1998-04-17 elongated.

It is preferred that the body further com~ri~es a plurality of vertical lands that ~eparate the ~anels.

It is preferred that the body further com~rise~
horizontal land~ above and/or below the panels.

It i~ preferred that the body further compri~e~
circumferential and/or axial reinforcin~ ribs.

It i~ preferred that the container further com~rises a neck-to-body transition.

It i~ preferred that the neck-to-body tran~ition be a shoulder.

- It i~ preferred particularly that the shoulder be frusto-conical.

It is preferred more particularly that the fru~to-conical shoulder com~ri~es a plurality of spaced a~art panels.

It is preferred that the neck be threaded to receive a ca~.

The polymeric material may be any suitable material ~uch as polye~ter and polypro~ylene.

The present invention is de~cribed further by way of example with reference to the accompanying drawings in which:

Figure l i~ a side elevation of one preferred embodiment of a bottle in accordance with the present invention;

CA 0223~2~3 1998-04-17 ~ 7 --Figure 2 is an enlarged cross-section along the line A-A o~ Fi~ure l;

Figure 3 is a graph which illustrates the predicted peff ormance the bottle shown in Figure 1 and a known 6-~anel bottles;

Figure 4 is a perspective view o~ another pre~erred embodiment of a bottle in accordance with the present invention; and Figure 5 is a section along the line 5-5 of Figure 4.

The bottle shown in Figures 1 and 2 is adapted to be hot-~illed with liquid and com~rises:

- i. a neck l;

ii. a generally cylindrical body 2;

iii. a neck-to-body tran~ition 3 in the ~orm o~
a generally frusto-conical ~haped shoulder;
and iv. a base 4.

The main feature o~ the bottle is that the body 2 comprises five panels, generally identi~ied by the numeral 5, which are responsive to changes in internal pres~ure in the bottle that occur when a li~uid is hot filled into the bottle at a temperature of at least 80~C and, after the bottle is sealed, cools to ambient temperature to prevent uncontrolled distortion of the bottle.

The body 2 comprises vertical lands 6 that separate the panels 5 and horizontal lands 7 that are above CA 0223~2~3 1998-04-17 and below the panel~ 5. It is noted that in the ~resent instance the term "landg~ i5 u8ed in a general sense and cover~ structure~ that are algo re~erred to as "~o~ts".

The panels 5 are generally elongate and are ~aced uni~ormly around the circumference of the body 2.
Fach panel 5 comprises:

i. a central section ll that i~ curved in transver~e ~ection - a~ shown in Figure 2 -and define~ a label su~ort; and ii. an outer ~ection 13 that enclose~ the central section ll and interconnect~ the central section ll and the vertical and horizontal lands 6, 7.

- The outer ~ection 13 of each panel 5 acts as a hinge and enable~ the central gection ll to move inwardly as hot filled liquid in the bottle contract~ a~ it cools to am~ient temperatures.

The bottle may be formed by blow moulding a polyester resin, such as polyethylene terephthalate.

In order to inve~tigate the per~ormance o~ the present invention the a~licant carried out computer modelling on the bottle shown in Figures l and 2 and on a selection o$ commercially available 6-~anel hot f ill bottles. The ~ur~oge of the computer modelling wa~ to predict the reduction in volume that the bottle~ could ~ccommodate be~ore collapsing into an unacceptable sha~e.

The result of the computer modelling are shown in Figure 3.

With re~erence to Figure 3 the various plot~

CA 0223~2~3 1998-04-17 g illu~trate the reduction in volume of each of four 750ml sealed bottles as pressure ig applied to the outside of the bottles.

The plots identified by the numerals i, ii and iii in the legend of Figure 3 illu~trate the ~redicted performance of three known 6-panel hot fill bottles and the plot identified by the numeral i~ in the le~ena of Figure 3 illustrates the predicted per~ormance of the preferred embo~im~nt of the pre~ent invention.

The graph ghows that the three known 6-panel bottles collapsed at volume reductions of the order of 22 to 26ml. This volume reduction i~ close to the typical volume reduction of a 750ml volume of a wide range o~
liquid~ that are routinely hot filled into bottles at a tem~erature of 80~C.
-The graph al~o show~ that the preferredembodiment of the bottle o~ the present invention ~hown in Figures 1 and 2 collapged at a significantly higher volume reduction of the order of 36mls. This bottle could accommodate the typical reduction in volume o~ the wiae range of liquids that are routinely hot filled into bottles at a temperature of 80~C.

The bottle ~hown in Figures 4 and 5 is conceptually the ~ame as the bottle shown in Figures 1 and 2 and the ~ame reference numerals are used to denote the same parts.

The bottle has a different overall shape to that of the bottle qhown in Figures l and 2.
J

The main structural difference is that the bottle has a different form of hinge that interconnects each panel 5 to the ~ertical and horizontal lands 6, 7 o~ the body 2 to that ~hown in Figures 1 and 2. Ag can best be ~een in Figure 5, the hinge is in the form of a double-S.

The performance of the bottle shown in Figures 4 and 5 was e~aluated against that of a commercially available 6-~anel hot-fill bottle.

A number of sam~le bottles shown in Figures 4 and 5 were blown, and the sample bottles and conventional 6-panel bottles were subjected to te~ting accordin~ to a ~t~n~d testing ~rocedure. The results are set out in the ~ollowing table.

CA 0223~2~3 l998-04-l7 WO97/l4617 PCT/AU96/00641 ~aluation ~ 5 Panel 6 Panel St~
Bottle Bottle Trial Weight (g) 35.5 35-3 r Bottle ~;men~ion8 (mm) Nom; n~l - Overall Height 191.91 194.2189.76 - Major Diameter 69.22 69.9 71.0 - Pinch Diameter 59.12 59.3 59.0 - Panel Diameter 67.71 67.6 69.0 Capacity at Fill Point 520 523 M;n;ml~m (20mm down ~rom top)(mL) 511 Brimful Capacity (mL) 534 537 M;n;m.. m Finish Dimen~ions (mm) - "T" Diameter 37.2 37.2 - "E" Diameter 34.9 34.9 - Bore 29.8 2g.8 Vacuum ~oad (in Hg)10.4 4.7M; ~; ~--m 6.5 Section Weightc (g)*~
' - Ba~e 6.9 7.1 - Label Panel 11.2 10.6 - Belt 2.3 2.1 - Top 15.0 15.3 ~h~rm-1 StabilitY Te~t a. Shall not burst OK OK
b. Shall not OK OK
develop rocker bottom~
c. Shall not OK OK
develop objectionable appearance d. Volume change (%) - Nett Shrinkage 1.9 2.8 maximum - Ba~e 1.0 0.9 Di~tortion - True Shrinkage 2.9 3.7 e. Overall height0.6 0.9 change (%) f. Body diameter 0.3 2.2 change (%) g Panel diameter2.7 2.8 0.8 change (%) ** Section~ defined by cut~ at 17mm, 109mm an 129mm from bottle of the bottle.

CA 0223~2~3 1998-04-17 With reference to the table, the heA~;ng "Vacuum Load" indicate~ that ~ignificantly higher internal ~re~ure, 10.4 Hg v~ 4.7 Hg, wa~ required to colla~e the r hot fill bottle ~hown in Fi~ures 4 and 5. The~e figure 5 are a clear indication that the hot-fill bottle ~hown in Figure~ 4 and 5 had ~ignificantly better ~tability under hot fill condition~ than the conventional 6-~anel bottle.

Many modi~ication~ may be made to the preferred embodiment de~cribed above without departing from the 10 ~pirit and ~cope of the pre~ent invention.

For example, whilst the label ~up~ort ~ection~ 11 of the bottle~ shown in Figure~ 1/2 and 4/5 repre~ent a relatively large proportion of the ~urface area o~ the panel~ 5, it can readily be a~reciated that the pre~ent 15 invention is not limited to ~uch an arrangement and the area of the label ~u~port section~ may be ~elected ax required.

Claims

CLAIMS:

1. A hot fill container formed from a polymeric material, which container comprises, a base, a body, and a neck, wherein the body comprises an odd number of spaced-apart panels, and the panels are responsive to internal pressure change in the container.

2. The container defined in claim 1, wherein the panels are responsive to internal pressure changes within the container that occur when, in use, the container is filled with a hot liquid at a temperature of at least 80°C. sealed, and the liquid cools to ambient temperatures thus reducing the volume defined by the container.

3. The container defined in claim 1 or claim 2, wherein the body is generally cylindrical.

4. The container defined in any one of the preceding claims wherein the panels are spaced apart around the circumference of the body.

5. The container defined in claim 4 wherein there is a uniform spacing between the panels.

6. The container defined in claim 5, wherein there are 5 panels.

7. The container defied in claim 6, wherein the capacity of the container is less than 1 litre.

8. The container defied in claim 5, wherein there are 7 panels.

9. The container defined in claim 8, wherein the capacity of the container is equal to or greater than 1 litre.

10. The container defined in any one of the preceding claims, wherein the panels comprise panel walls that are adapted to flex or deform inwardly.

11. The container defined in claim 10, wherein the panel walls are concave.

12. The container defined in any one of claims 1 to 9, wherein the panels comprise label support sections that are relatively rigid and hinge assemblies that interconnect the label support sections and adjacent sections of the body and allow the label support sections to move inwardly.

13. The container defined in any one of the preceding claims, wherein the body further comprises a plurality of vertical lands that separate the panels.

14. The container defined in claim 13, wherein the body further comprises horizontal lands above and/or below the panels.

15. The container defined in any one of the preceding claims, wherein the body further comprises circumferential and/or axial reinforcing ribs.

16. The container defined in claim 15, further comprises a neck-to-body transition.

17. The container defined in any one of the preceding claims, wherein the neck is threaded to receive a cap.